The objectives of the proposed study are to: 1. identify neural elements in the brain involved in tonic suppression of ponderal and skeletal growth in adult hamsters through their restraining influence over feeding and secretion of growth hormone and insulin, 2. document the behavioral, endocrine, and somatic correlates of growth following the interruption of neural pathway responsible for tonic suppression of growth to the mechanism of long-term regulation of body weight, body size, and body composition in adult hamsters. These objectives will be sought by transection of the following four types of brain connections with the septal area with a retractable microencephalotome: a) septocortical, b) septohippocampal (and septohabenular), c) septoamygdalar, and d) septohypothalamic (and septomesencephalic) connections to determine which transection is necessary for acceleration of growth seen after lesions of rostral septal area in adult hamsters. Measurements of behavioral, endocrine, and somatic concomitants of growth will be done, respectively, by monitoring of food consumption, of concentrations of growth hormone and insulin in the serum and of growth hormone content in the anterior pituitary by the double-antibody radioimmunoassays, and of weight and radiographic length changes. Location and size of knife-cut damage to brain tissue will be determined by using the strains for degenerating nerve fibers on serial sections of brain tissue.